For compensating for distortions of ultrasonic transducer signals by measuring thickness of a membrane cap and 3D oil covering the ultrasonic transducer in real time without additional hardware, according to an embodiment of the present disclosure, an ultrasonic imaging apparatus may comprises an ultrasonic probe configured to have an ultrasonic transducer with a plurality of elements, a membrane cap provided in a form that covers the ultrasonic transducer, and three dimensional (3D) oil provided between the ultrasonic transducer and the membrane cap； a controller configured to obtain thickness data of at least one of the membrane cap and the 3D oil to compensate for a distortion of a signal transmitted or received by the ultrasonic transducer.
